Furnace-grate



(No Model.)

J. THURELL'.

FURNACE GRATE'.

No. 460,408. Patented Sept. 29, 1891.,

UNiTEn STATES PATENT Ormcn.

JOHN TI-IURELL, OF ZYLONITE, MASSACHUSETTS.

FURNACE-GRATE.

SPECIFICATION forming part of Letters Patent N 0. 460,408, datedSeptember 29, 1891. Application filed January 3, 1891. Serial No.376,635. (No model.)

.To ztZZ whom it may concern:

Be it known that I, JOHN THURELL, a citizen of the United States,residing at Zylonite, in the county of Berkshire and State ofMassachusetts, have invented new and useful Improvements inFurnace-Grates, of which the following is a specification.

, My invention relates to certain improvements in the construction offurnace-grates, one purpose thereof being to provide a novel and simpleconstruction by which the grateframe shall be very materiallystrengthened and its warping prevented. It is my purpose also to providea simple and inexpensive construction whereby the frame of the grateshall be strengthened and stiffened and a fastening provided at theangles thereof by one and the same device.

To these ends my invention consists in the several novel features ofconstruction and new combinations of parts hereinafter fully set forth,and then particularly pointed out and defined in the claims followingthis specification.

To enable others skilled in the art to which my said invention belongsto make and use it, I will proceed to describe the same, reference beingmade to the accompanying drawings, in

which Figure 1 is a view, partly in side elevation and partly inlongitudinal vertical section, showing the construction of thegrate-frame, the manner of uniting the parts thereof, and the grate-barsmounted therein. Fig. 2 is a view in transverse vertical section showingmore fully the construction by which-the bars of the grate-frame areunited, the gratebars being shown in dotted lines. Fig. 3 is a detailperspective of the parts composing the grate-frame, the grate-bars beingremoved.

In the said drawings, the reference-numeral 1 denotes the end pieces,and 2 indicates the longitudinal side pieces, of a grate having my novelconstruction. These parts in former constructions have sometimes beencast in a single piece; but when made in accordance with my inventionthey are constructed separately and united in the manner hereinafterdescribed to produce the form of frame shown in Fig. 3, in which theside bars and end bars of the frame are cast separately, each in asingle piece, the end pieces being provided with tenons 4, adapted toenter mortises 5 in the side pieces, and being retained in thisengagement by means of a metallic rod 6,1ying in a horizontal channel orgroove 7, formed in the inner face of each end piece. The ends of eachrod enter apertures in the ends of the side pieces and project somewhatbeyond the outer faces thereof, being adapted to receive nuts upon saidextremities, which would then be threaded for such purpose. These barsmay, however, be fastened in other ways-as, for example, by upsetting orheading theirprojecting ends. In order that the nuts or upset ends maynot project beyond the outer faces of the side bars, shallow recesses 8may be provided in the outer face of each side bar j ust above the endsof the tenons 4. These rods are of great use in preventing the warpingof the grate, as well as in permanently uniting the parts of the latter.The journals of the rock-shafts are inserted in their seats in the sidebars before the parts of the frame are brought into position forpermanent union.

While this grate, having the construction set forth, may be used in anyordinary form of furnace, I have employed it in connection with thefurnace for which I made application for Letters Patent, filed December27, 1890, Serial No. 375,973, and allowed April 7, 1891.

By placing the tie-rods '7 in channels in opposite bars or sides of theframe they are not only removed from the area inclosed by the frame, butare protected from the direct action of the fire, their serviceablecondition being greatly prolonged thereby. Moreover, by combining thetenons 4 and rod 6, I am enabled to secure a fastening which is far moreefficacious than any that can be produced by either device alone. Thesedevices give a rigid joint, which will not only resist the rackingstrains produced by shaking and dump ing the grate, but will prevent thewarping of the same. The frame may be readily dismembered, however, andagain connected with great case.

That I claim is 1. In a furnace-grate, the combination, withseparately-formed end bars and side bars provided with tenons upon oneentering mortises in the other, of tie-rods lying in channels in opposite bars of the grate, the ends of said rods projecting inparallelism with the tenons and passing through the ends of the tworemaining sides to form fastenings to draw and hold 5 the side and endbars together at the angles of the grate, substantially as described.

2. In afurnace-grate, the combination, with separately-formed end barsand side bars, two of said bars being provided with tenons upon IO theirends entering mortises in the ends of the remaining bars, of tie-rodslying in channels in the bars, having tenons, the ends of said rodsprojecting and entering openingsin the ends of the mortised bars, thelatterbeing provided with recesses adjacent to the inorr5 tises, wherebythe fastenings afforded by the said rods shall not project beyond theouter surface of the grate,substantially as described.

In testimony whereof I have hereunto set my hand and affixed my seal inpresence of 20 tWo subscribing witnesses.

JOHN Tl-IURELL. n s] Witnesses:

ED. GUILBo, J. A. WIoKEs.

